Hello people -
I recently had to change the cam chain tensioners on my bike. My brother the master mechanic came by and told me what to do, then basically took over. He looked inside and pointed out the my front guide was also broken, and had me order all 4 parts. And oh yeah, he says, the front guide is slotted into the engine and thats what broke. So we have to take the top end off, and that means we're takin the engine out.
So we do that. The parts come in a few days later. My brother comes out and says I think this valve right here is gonna be cracked or something. So we check it out and yes, the trumpet end of it is smashed up and its split. This is on the exhaust side, the 2/2. Money's tight right now so of course he insists I get 16 new valves, but I end up being only to afford replacing the exhaust side.
We put the new valves in, we used valve grout and got it all set up, then he did a 'poor man's compression test', and pours water into each hole and everything seemed ok. When we checked the lash, the gaps were all over the place. I can only imagine the shims got jumbled, mixed up. We used .002 and .006 for a bracket. Then he sanded some down with an upside down belt sander. Rhey were all sanded on the bottom. They didn't look too are worthy to me anymore so I said something and he says, 'well looks like you need 5 new shims, but get 6', and he told me the sizes. I got them on eBay a few days later. He puts them in and one does not add up to what he calculated. I ask him why that happened, long story short, we have a big blow up argument and he splits, and I think I am gonna have to complete this myself.
I only explain this because I have seen various posts where the OP is accused of trying to perform certain mechanical feats on their bikes that are deemed by senior members as being above their paygrade, so to speak. I'm not doing this because I got bored with my bike, it's a stripped down plain jane cb900c and I like it that way. I'm mechanical a.d I've done all sorts of stuff to my bike, but nothing this invasive. I'm doing this because I'm stuck, and I need my bike for transpo. So that being said, here's my question:
What is gained and lost concerning valve lash? I'd like to know how it affects both the intake and exhaust valves. Can I be off by .001 one way or the other and still put the bike back together?
Thank you!
Sent from my SAMSUNG-SM-G891A using DO THE TON mobile app
I recently had to change the cam chain tensioners on my bike. My brother the master mechanic came by and told me what to do, then basically took over. He looked inside and pointed out the my front guide was also broken, and had me order all 4 parts. And oh yeah, he says, the front guide is slotted into the engine and thats what broke. So we have to take the top end off, and that means we're takin the engine out.
So we do that. The parts come in a few days later. My brother comes out and says I think this valve right here is gonna be cracked or something. So we check it out and yes, the trumpet end of it is smashed up and its split. This is on the exhaust side, the 2/2. Money's tight right now so of course he insists I get 16 new valves, but I end up being only to afford replacing the exhaust side.
We put the new valves in, we used valve grout and got it all set up, then he did a 'poor man's compression test', and pours water into each hole and everything seemed ok. When we checked the lash, the gaps were all over the place. I can only imagine the shims got jumbled, mixed up. We used .002 and .006 for a bracket. Then he sanded some down with an upside down belt sander. Rhey were all sanded on the bottom. They didn't look too are worthy to me anymore so I said something and he says, 'well looks like you need 5 new shims, but get 6', and he told me the sizes. I got them on eBay a few days later. He puts them in and one does not add up to what he calculated. I ask him why that happened, long story short, we have a big blow up argument and he splits, and I think I am gonna have to complete this myself.
I only explain this because I have seen various posts where the OP is accused of trying to perform certain mechanical feats on their bikes that are deemed by senior members as being above their paygrade, so to speak. I'm not doing this because I got bored with my bike, it's a stripped down plain jane cb900c and I like it that way. I'm mechanical a.d I've done all sorts of stuff to my bike, but nothing this invasive. I'm doing this because I'm stuck, and I need my bike for transpo. So that being said, here's my question:
What is gained and lost concerning valve lash? I'd like to know how it affects both the intake and exhaust valves. Can I be off by .001 one way or the other and still put the bike back together?
Thank you!
Sent from my SAMSUNG-SM-G891A using DO THE TON mobile app
